From: Eric Dumazet <edumazet@google.com>
Subject: Re: SLAB_TYPESAFE_BY_RCU without constructors (was Re: [PATCH v4
 13/17] khwasan: add hooks implementation)
Date: Tue, 31 Jul 2018 10:41:54 -0700
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To: Christoph Lameter <cl@linux.com>
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On Tue, Jul 31, 2018 at 10:36 AM Christopher Lameter <cl@linux.com> wrote:

>
> If there is refcounting going on then why use SLAB_TYPESAFE_BY_RCU?

To allow fast reuse of objects, without going through call_rcu() and
reducing cache efficiency.

I believe this is mentioned in Documentation/RCU/rculist_nulls.txt